Another Brisket question

Did my 2nd brisket on the YS640, Prime full packer from costco trimmed down to 8.6lb
The point came out absolutely melt in your mouth good, but the majority of the flat was tough and dry, mostly in the middle section of it
I started probing it around 198, was tough so I took it to 203-205 and it was feeling more tender around the outside edges of the flat, but it was 7pm, wife and kid were hungry and it still needed a rest so I pulled it
So my question, did it just need more time or did I overcook it?
I put it on at 6:15a and pulled it at 7pm
The point came out absolutely melt in your mouth good, but the majority of the flat was tough and dry, mostly in the middle section of it
I started probing it around 198, was tough so I took it to 203-205 and it was feeling more tender around the outside edges of the flat, but it was 7pm, wife and kid were hungry and it still needed a rest so I pulled it
So my question, did it just need more time or did I overcook it?
I put it on at 6:15a and pulled it at 7pm